Composite right/left-handed dual-band metamaterial antenna with improved gain and efficiency

In this article, a duals-band metamaterial antenna with a new composite right/left-handed (CRLH) unit cell configuration is proposed. The antenna is a coplanar waveguide (CPW) base which uses quarter wave resonators without via. Both sides of the CPW ground plane are short circuited to the CRLH-transmission line. The dimension is 31 mm x 22 mm x 1.52 mm, with electrical size of 0.23 lambda(o) x 0.17 lambda(o) x 0.011 lambda(o) at 2.26 GHz, and which is compact in size. Resonance frequency of the negative mode can be altered by controlling the loop currents. Peak gains of 1.74 and 2.69 dBi are obtained at 2.26 and 2.89 GHz. Radiation efficiencies of 64% and 92% are obtained at 2.26 and 2.89 GHz, respectively. The simulated and measured return losses, as well as the radiation patterns, are presented and compared. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1575-1579, 2014